Recoil mechanism for cannons.



APPLIGATIQN FILED DEC. 1, 1904.

5 SHBETS- SHBET 1.

i- NN mum v ns m Lrmmwasumamn PATENTED APR. 24, 1906.

F. B. YINGLING. REGOIL MEfiHANISM FOR CANNONS" APPLICATION I ILED DIE-10.1, 1904.

i van fo'c N o) m 5w I 1. gm M PATENTED APR. 24, '1906.

' F. B. .YINGLING.

REGOIL MECHANISM FOR GA NNONS.

APPLIGA'TION FILED 13110.1. 1904.

' v 5 SHEETS-SHEET 3- 0 3 Witnesses 'PATENTED APR. 24,1906.

P. B. YINGLING. RECOIL MECHANISM FOR-GANNONS.

APPLICATION FILED 1330.1, 1904'.

5 SHEETS-SHEET 5.

Witmeooao v @citizen of the United States, residing tempo- 'rarily at Dusseldorf, Germany, have invented.

. UNITED STATES PATENT ()FFIGE. FRANK B. Y NGLINe, or DUSSELDORF. GERMANY." ASSIGNOR TO RHEINISCHE METALLW'AREN-UND MASCHINENEABRIK, or Dfis- SELDOREDERENDORF,GERMANY.

'nseou; mEc'HANIsM oe cANNoNs,

Specification of Letters Patent.

To all whom it'mcty concern: v

Be 1t known that I, FRANK B. YINGLING, a

certain new and useful Improvements in Recoil Mechanism for Cannon, of which the fol- 1 lowing is a specification.

-The present invention relates to im prove- 'ments 1n recoil mechamsm ,for cannon, and

particularly to an adjustable brake or con- 1.

trolling device for regulating the recoil. It is customary to chec or reiplate the recoil of such guns by controlling t ough the actuation of a suitable valve the passage of liquid from one side of a piston working withln a cylinder that recoils with the gun to the other side of such-piston. In order to reduce the strains on the carriage in the case of field-guns,

it is customary to so arrange the valve that the-pressure of the liquid is maintained practica 1y constant or uniforml decreasing a small amount throughout the ib the gun it isnecessary to vary the length of reco1l,that is, when the muzzle of the gun is elevated the length of recoil must be less than that permitted or necessary, for stability when the gun is in a 'horizontal position to The object of the present invention is to provide means by which the length of the recoil will be automatically varied with vari ations in the elevation of the gunand' in which the pressure in the recoil-cylinder will be maintained practically uniform or uniformly decreases a small amount throughout the recoil regardless of the position or elevation of the gun. I i

In the accompanying drawings, Figure 1 carriage of a field-gun provided with a recoil mechanism embodying the present invention. Fig. 2 is a horizontal sectional view of the supporting-cradle, the recoil-cylinder, and parts contained therein on an enlarged scale. "Fig' 3 is a front elevation, partly in section. Fig. 4 is a sectional view o the line 4 4 of Fig. 2. Figs. 5 and 6 are detail views. Fig. 7 is a view of the developed adjustable curved surface. Fig. 8 is a View,

partly insection, of the recoil-checking mechism-of a gun, illustrating a mod fied form of ngth of recoil. In changing the elevation of the muzzle of the-invention. Fig. ,9 is a section on the line 9 9 of Fig. 8. Figs. 10 to 13 are sectional views on lines 10 10, 11-11, 12 12, and 13 13.

Patented April 24, 1906.

Fig. 17 is a sectional view on the line '17 17 of Fig. 16. Fi 18 is a sectional view, onan enlarged scaI e, of the device connecting the gun-elevating devices'with the valve-actuating mechanism of the recoil-cylinder. Fig.

19 is a section on the line 19 T9 of Fig? 18. Fig. 20 illustrates a modification of Fig. 16.

Figs.:21,-2 2, 28 are sections through Fig. 20'.

Fig. 24 is'a detail. views of a modificatiom,

Referrin to the drawings, in which like reference 0 aracters' designatecorresponding parts in the several figures, and particularly to Figs. 1 to 7, 1 designates the gun, WhlCl'llS mounted to slide on a cradle 2, supported to rock about a horizontal axis on a suitable frame 3, provided with atrail 4 and mounted on carrying-wheels 5; -As all of the parts before referred to may beof the ordinary or any suitable construction", it is not deemed necessary to describe or illustrate them in detail. Within the cradle 2 is arranged a recoil-cylinder 6, which is connected with the gun-bar rel to move therewith longitudinally of the cradle and within which cylinder is arranged a piston 7, carried by .a rod 8, secured to the forward end of the cradle. Said piston is hollow or provided with an internal chamber from the rear communicating with the forward end of the cylinder 6 through orts ,which are controlled by a valve 9. ithin the c linder is arranged a body of suitable li uid generally oil or water and glycerin, w ich in passing fromone side of the'head of the piston 7 to the oppositeside thereof with.- in said cylinder acts to check and control the movements of the cylinder in recoil, and there'- fore of the gun, which is connected therewith. Within the cradle 2 about saidrecoil-cylinder, 6 is arranged the usual counter recoil spring or springs 10, which at the forward end abut during the recoil motion of the gun and cylinder. In the embodiment of the 1nvent1on illustrated in Figs. 1 to 7 a ring or plate is ar-v Figs. 25, 26, 27,28 are 4 ranged at the rear end of said counter-recoil extends the rod or stem 8 o the piston with the valve-stem 9. In the embodiment of the invention illustrated in the aforesaid figures the passage of liquid through the ports in the piston-head is controlled by a cylindrical valve 9, consisting of a tube surrounding the piston and provided with suitable openings or communicating with said ports, the length of said cylinder being such that its forward end extends beyond the forward end or head of the recoil-cylinder6, and to the said valve in advance of the recoil-cylinder is secured a radially-extending arm 14. The inner end or hub-like portion of said arm 14 is provided with aseries of teeth 15, which engage with similar teeth 13, formed on the bar or plate 12 about the central opening therein, and the outer end of said arm 14 is adapted to engage with an arm 16, mounted on a rock-shaft 17, extending longitudinally of and journaled in suitable hearings on the cradle 2. Said shaft 17 is preferably made polygonal'in cross-section throughout the greater portion of its length, and mounted to slide thereon is a leverarm-18, which is engaged by an arm 19, projecting laterally from the'recoil-cylinder 6. On the other free end of said arm 18 is mounted a roller 20, adapted to bear against and travel longitudinally of a cam plate ,or surface '21, mounted between the cylinder 6 and the cradle 2. It will be seen that an variation in the radius of the portion of t e plate 21 traversed by said roller 20 during recoil of the gun will act to rock the shaft 17 and through the arms 16' 14 adjust the valve 9 about the piston, and thus control the passage of liquid in the cylinder 6 from one side of the piston to the opposite side thereof. The pressure exerted by such movement of the roller 20 is in opposition to that exerted by the counter-recoil springs on the bar or plate 12, which tend to hold the valve 9 in the it occupies prior to firing the gun, said valve and plate being connected, as aforesaid, by the teeth 13 15. The counter-recoil springs, through the rods 1 1 tend to draw the plate 12 toward the breech or rear end of the cradle. The rods 11 are guided and held against rota tion around the axis of the recoil-cylinder by the dia hragni extending across the cradle in front 0 the recoil-cylinder and serving in the embodiment of the invention illustrated in Figs. 1 to 7 to sup ortthe forward end of the cam-plate 21. T e tendency of the plate 12 to move rearward under the force of the springs is checked-by the arm 14, the inclined surfaces or teeth 13 15 of said parts being in contact. The result of the rearward force osition.

exerted on the plate 12 thus tends to rotate the arm 14 about the axis of the cylinder, the

direction of which depends on the angles of the curved inclined surfaces 13 15 whether they-are right or left hand. As the arm 14 is engaged by the lever-arm 16 the rotative action is transmitted to the shaft 17 and in turn to the roller 20 through arm 18. Therefore as the roller 20 follows the contour of thecurved surface presented, the closing of the valve being efiected by the cam-surface pressing the roller 20 outward .until thegun is brought to rest. Said plate 21 is curved on its inner face to conform to the-adjacent sur-- face of the cylinder 6 and has formed on its outer surface a plurality extending curves of difierent lengths and radii, each being of'such form as to properly actuate the valve 9 at one ofeither of the several positions of elevation ordepression which v the gun may assume. As shown, the plate 21 is provided at its ends with rings that surround the recoil-cylinder, being suitably supported within the cradle 2, and means are provided for rotating said plate 21 about the axis of the cylinder 6 as the elevation of the gun is varied in order to bring into contact with the roller 20 that portion of said plate presenting the proper longitudinal curve to effect the operation of the valve 9 and close the ports in the piston 8 to check the recoil of the gun at the proper time. In the embodiment of the invention shown in said Figs. 1 to 7 the plate 21 is provided at its forward end in advance of the cylinder 6 with an upwardly curved or flaring ortion on which are formed suitable teeth ,t at mesh with the teeth of the segmental spiral gear 22, mounted on a transverse shaft 23, journaled in bearings on the cradle 2; said shaft carr ing also a gear-segment24, adapted to mes with the teeth of a rack-bar 25, the rear end of which is connected to a yoke that is pivotally connected to the sup orting-frame of the gun. As the gun is roc 'ed about the horizontal aids on which it is supported to vary the elevation of the muzzle either by raising or depressing. the same it will be seen that the rack 25 will be drawn rearwardly or pllgshed forward, as the case may be, and t ough the gear 24 the shaft 23 will be rotated and the gear 22 will adjust the plate 21 about the cylinder 6 to bring the proper longitudinal curve thereon into position to act upon the roller 20.

Various modifications of the means for presentingfor each adjustment or variation elevation of the gun a curved surface havof longitudinallying the configuration required to properly actuate the check-valve of the recoil mechanism may be substituted for that above de scribed and shown in Figs. 1 to 7. I

In the form of the invention illustrated in Figs.'8 to 13 the recoil-cylinder 6, is mounted so as to be free to rotate while moving longitudina lly of the cradle with the gun during recoil and counter-recoil, and the valve 9 is connected to said cylinder to be rotated thereby about the head of the stationary piston, which is of the same form as that previously described. As shown, the valve is provided at diametrically opposite points with suitable radial rojections which engage grooves or ways ormed in theinner surface of'the recoil-cylinder. Instead of employing a single plate with lon itudinal cams which i is adapted to be rotate about the axis of the recoil-cylinder, rollers 26 27 are mounted on opposite sidesof the roller 20, carried by the cylinder 6, each of said rollers 26 and 27 hav- ."ing a plurality of longitudinally-extending curves formed on its outer surface and each being mounted to rotate about a longitudinal axis. At one end each of said rollers 26 27 is provided with a, spiral gear 28, with -Which" gear meshes a gear 29, mounted on a shaft also carryln a" spur-gear 30, which meshes with a rackar similarin function to the rack 25'- of the embodiment of themvention illustrate'd in Figs. 1 to 7. As the elevationof the gun is varled the rollers 26 27 1 will be rotated to provide-between them .a

way orpassage for the roller 20, which will have the required longitudinal configuration or curve to rotate the recoil-cylinder 6' during its'longitudinal rearwardmovement to properly operate the valve 9.

Instead ofo crating the shaft 23 by the arrangements of gearing heretofore described that illustrated in Fig. 14 may be employed. Referring to said figure, there is secured on the outer-end of'the shaft 23 a bevel-gear 28, with vwhichmeshes a bevel-gear29 on the forward end of-a shaft 29, that ismounted in suitable bearin s-secured to the gun-cradle 2.

On the rear en of shaft 29 is secured a spiral gear 30, that meshes with a gear-segment 31,

'stationarily'secured to one of theside plates ofthe frame 3 andexte'nding concentric with V the-axis about which the gun is adapted, to

rock.

Referring to the embodiment of the invention illustrated in Figs. 15 to 18, it will be seen that a series of grooves 32, having their outer walls of the same form as the longitudinally-extending cams 21 of the two first forms andoii'difier'ent lengths, are formedin the inner face of the wall ofthe reco l-cyhm .der 6", and that instead of employing a valve adapted to be rotated about the piston at each recoil operation of the gun the pistonhead '9", itself forms in connection with the outer curved walls of the exposed groove 32 the valve-for controlling the movement of fluid in said cylinder. Within the cylinder .is arran ed a'second cylinder 33,- having formed therein a longitudinal slot of a width corresponding to ,the width of each ofthe grooves 32 and adapted to be adjusted into alinement with either of said grooves in the Tecoil-cylinden. Said slot does not extend throughout the length of the cylinder 33, but has a solid continuous unbroken wall between the rear end of the recoil-cylinder 6" and the position which the piston 9-" occupies when the gun is in normal battery position. In this form of the invention the recoil-cylinder, like that in the form first described, doesnot rotate during recoiling of the gun, and the inner cylinder 33 is connected with the piston to be rotated thereby, ro-

tary movement; being communicated to the piston rod or stem by means similar tothose described for rotating the valve in the form of the invention illustrated in Figs. 1 to 7. As shown, the piston 9" is rovided with a radial projection 34, adapte to enter the slot in said 0 'linder 33, whereby the piston and said cylin er are connected to rotate together, but the piston is free to move "longitudinally of the cylinder. The recoil-cylinder 6" being held against rotation, itwill be seen-that if rotary;v movement be communicated to the piston-frod during variations 1n the elevation of the gunsuch movement will be transmitwith either of the grooves 32.- Therefore Q means are provided for imparting intermittent rotation to the inner cylinder, andthe amount or extent of each intermittent rotary movement of suchcylinder is equal to the One means 'oreflecting this intermittent rotation of said cylinder 33is illustrated; 'Instead of employing a rackebar like that shown the toothed section 35 having a stem which "extends centrally through a cylindrical shell distance so arating adjacent grooves 32. V.

in Fig. 1 a two-part bar or li'nkis provided,

36 and provided within'said casing with a radially-projectingjdisk 3.7, between which and opposite ends fof said. shell are arranged coiled "springs 38 The rear end oflthe shellor casing'36is connected 'with a link 40, the other end of whichi'sadapted to be em I aged by a hand leverel, fulcrumed on'the ame of, the gun-carriage.

It is customary to facilitate rapid loading to provide means for disconnecting the servi -ice mechanism for elevating and de and bringing the gun to a substantially horiing such movement of the gun to loading sition the said hand-lever is adapted to is i connect the inner end of the link carrying the rack 35 when such hand-lever is being usedthat is, the lever 41 is geared to a lever which engages the gun and the link 40 is provided 1 at its rearend with means that extend into a curved slot 40*, formed in a portion of the frame of thegun-carriage. The lever 41 is provided in its forward edge with a seat or recess that receives and acts as an abutment for the rear end of the link 40, which end is thus normally held between the lever 41 and forward end of the slot 40. When, however, the hand-lever 41 is operated to bring the gun to loading position, the link 40v is first disconnected from the frame and its rear end moves freely along the slot 4O as the lever 41 is rocked, the rack being held in fixed relation to the gear 24 by the stop .43 during such movement.

shaft 44, having at its forward end a stud or' lug 45 and at its rear end a threaded section connected by inclined passages.

The casing for the rack 35 is made in the cross-sectional form shown in Fig. 19, having its interior divided into two'passages by a web 42. The rack 35 is adapted to movein the upper chamber or passage and is provided at its free end with a spring-pressed stop. 43, adapted to engage with either of a series of apertures formed in said web 42-. Into the passage below said Web 42 projects a 46, engaging 'the'walls of an aperture in the 'front head of the spring casing 36. The

aforesaid apertures in the web 42 are in alin'ement with circular grooves or ways formed in the rack-casing, and said circular ways are Normally the stop 43 is in en gement with one of the apertures in the a oresaid web 42 and the trip-lug 45 is in the osition shown in Fig. 19. The rack-35 is thus ocked against movement relative to the gear-24 engaged thereby, and therefore the shaft 23 and gears 22 21 can not be rotated until said stop 43 is withdrawn. When the parts are in this engaged position, if the elevation of the gun is varied the stem of the rack 35 will be moved longitudinally throu-gh the casing 36, compressingone or the other of the springs 38 39, according as the muzzle of the gun is being elevated or depressedthat is, the gear .24 and rack 35 are locked against relative movement by the stop 43 during the variation in elevation of the gun, and as the swinging movement of the gun varies the distance between the shaft 23' and rear end of link the stem of the rack is moved bodily through the casing 36,

placing one of the springs therein under tenmam ' sion. The rod 44 is also moved through the head of the casing 36 engaged thereby and b reason of its threaded section 46 is rotate causing the lug to release the stop 43 and permitting the springs 38 39, previously put under tension, to actuate the rack 35 and gear 24, as described. By such longitudinal movement of the rack-bar rotary motion is communicated to-the trip-rod 44, and when the lug 45 comes into engagement with the stop 43 such stop is disengaged, and the rack 35 is then actuated by the previously-conipressed spring'38 or 39 to rotate the gear 24 and through the gearing 22 21 turn the inner cylinder 33 to bring the desired roove 32 into .alinement with the'slot in said cylinder 33-. Such movement isaccomplished during the time that the stop 43 is movin from one of the apertures in the web 42 to t e next of said apertures with which it engages on com-,

ing into alinement therewith, and the triplug 45 simultaneously moves through one of the inclined passages into position beneath such stop 43.

In the embodiment of the invention shown in Figs. 20 to 24 it will be seenthat the grooves 32 are made narrow, and the slot in the inner cylinder 33 extends over two or more of these grooves. the'longitudinal grooves form on their outer face or. Wall a curved surface which is substantially the same as that shown in Fig. 7- that is, each element of its surface is proportioned to give the correct area in connection with the sides of the little dividing-walls and the side of the projecting lug 34 to control the flow of the braking h'quid, as heretofore described. It will be seen that the slot in the inner cylinder can move over-a certain number or an part of the curve, and the length of recoi will be controlled accordingly. The movement can be continuous as the ele-. vation of the gun varies. I

Figs. 25 to 28 show a modification of the previous form, the curved surface and the little dividin -walls being placed within the iston-rod, w ich rotates, the curve and roller eing retained stationary by the cylinder 6" the port through the iston-head affording communication from t e forward side to the bore oi the iston-rod. It is evident that the liquid will e controlled by passing through the orifice formed by the curved surface on The entire series of that which is theoretically correct-that is,

variations the elevation of the gun do not vary the dimensions of the passages through which the fluid passes from one side ofjthe ,con'trolling piston to the other prior to the commencement of the recoil movement; but.

such passages are after the beginning .of the recoil movement at all elevations of thegu'n opened to their maximum extent in a dis-' tance' equal approximately to one caliber of the gun or at the instant the projectile leaves the gun.

The parts are so proportioned and arranged that the orifice orpassage for, the checking fluid increases in size so long as gas generated by the explodingcharge acts within the bore ofthe gun, the maximum of such Y orifice being reached as the projectile leaves the gun, and thereafter said orifice is reduced until the gun comes to rest. The maximum orifice variesin size and is located at difl'erent points in relation to theori in of thle -ree coil niovement, depending on t eleng lh of "recoil" It. can be shown that the len th of rc0il ivhile the gases generated by t e explosion of thecharge are acting on the gun is equal to a proximately one caliber of the Theb from one side of the piston to the other, re lating'and stopping such flow during recoi at the pro er timesbymeans brought into action on y whenthe 'un occupies a certain position'instead of re ucing the size of. the pas? sage for such liquid prior to the beginning of the recoil movement. abl so adjusted that no variation in the reco' -checking devices is effected by variations inelevation not'exceeding ten degrees from the horizontal. 1 I 1 i The foregoing description and the drawings illustrate six diflerent embodiments of the invention. It will be evident, however, that other modifications are possible and also that.

the invention is not linnted touse with fieldguns of the'character illustrated in the drawings, but is applicable to cannon of any class tyl i .Whatlblaim -is' I =1. The combination with a cannon, of fluid recoil-checking devices includin means for changing the length 'of recoil as t e elevation of the'gun-is varied, said means bein adapted 'tdprovide a'fluid-passage of orm' diniensions at the beginning of each recoil.

2' The combination with a cannon, of fluid recoil-checking devices includin means for providing a fluid-passage of uni orm dimen- 1 means for closing said ent distances of rearward travel 0 the gun in sions at the beginning recoil as the elevation of the gun is varied.

- 3. The combination with a cannon, of fluid recoil-checking devices includin means for providing a fluidpassage of mu oim dimensions at the beginning of each. recoil, and

means adjustable about the axis of the recoil cylinder for closing said fluid passagerat difraking or checking of the recoil I s efleted by regulating the flow of liquid- The parts are preferof each recoil, and uid-passa e at diflerierent distances of rearward travelof the gun 'lH recoil as the elevation of the gun is varied.

4. The combination with fluid recoil-checkingdevices for cannon, of means operating I durlng the recoil and controlled by variations in the elevation of the gun for, re ulating the dlmenslons of the fluid-passage oi said check ing devices and adapted to vary said passage from its'maximumto its minimum size at dlflerent distances in the rearward travel of the gun in recoil.

5. The combination with a cannon and ranged outside of the recoiling mechanism for controlling the position of said guide-surfaces and adapted'to be adjusted as the elevation of the gun is varied to cause; the length of recoil to vary in accordance with changes in the elevation of the gun. l

7. The-combination with acannon, and

fluid recoil-checking devices therefor including a rotaryvalve, of means controlled by variations-in the elevation of the. for rotating-said valveduring the recofi ent speeds, said means being adapted toreturn said valve to the same normal position at the completion of each counter recoil movement. Y

8. The combination with a cannon, and fluid recoil-checking devices therefor including a rotary valve, of means adjustableabout the axis of the recoil-cylinder, for controlling the closing of said valve, the length of time re'quiredto complete a movement of said valve depending, on the adjustment of said controlling means, and devices for automatically adjusting said controlling means-as the elevation of the gun is varied. I

9. The combination with fluid recoil-chec'ldng devices, of a roller reciprocating with the gun and movable about an axis. extending parallel to the-len th' of the gun, means actuatedwby saidangu ar movement of the roller for operating the valve mechanism of the recoil devices, and means for changing the extent of. said angular movement of the roller during the recoilto vary thetimeof operatingthe valve. v

a cannon, and

at dilfer- 10. The combination with a cannon, and I fluid recoil-checking'devices, f a roller reciprocating-with the gun andi'riiovable about an axis extending parallel to I length of the gun, means actuated-by saill angularmovement of the roller for operating the valve ranged outside of the recoil-cylinder and re;

clprocatm with the gun, said roller being movable a out an axis extending parallel to the length of the gun, means actuated by said angular movement of the roller for operating the valve mechanism of the recoil devices, and means for chan ing the extent of'said an ular movement 0 the roller during the re' 001 to vary the time of operating the valve.

12. The combination with a cannon, and fluid recoil-checking devices, of a cam-surface extending longitudinally of the recoil devices, a roller reciprocating with the gun in contact with said cam-surface, means actuated by said roller for o crating the valve mechanism of the recoil evices, and means for adjusting said cam-surface to vary the path of movement of said roller; for the purpose described.

13. The combination with a cannon, and fluid recoil-checking devices, of a guide extending tparallel to, the length of the nand provide with a plurality of" longitu inallyextending curves or cam-surfaces, means for actuating the valve mechanism of the recoil devices including a part adapted to reciprocate with the gun in contact with said guide, and means for adjusting said guide, to bring either of the cam-surfaces thereon into operative position. i

14. The combination with'a cannon, and fluid recoil-checking devices, of a guide adjustable about an axis extending parallel to the length of the gun and provlded with a plurality of longitudinally-extending curves or cam-surfaces, means for operating the valve mechanism of the recoil devices including a part adapted to reciprocate with the gun in contact with said guide, and means for rotating the guide to brlng any desired one of the cam-surfaces thereon into operative position.

15. The combination with a cannon, and fluid recoil-checking devices, of aguide adjustable about an axis extending parallel to the length of the gun and provided with a plurality of longitudinally-extending curves or cam-surfaces, means for opeFating the valve mechanism of the recoil devices including a part adapted to reciprocate with the gun in contact with said guide, and means for rotating said guide as the elevation of the gun is varied to bring into operative position the cam-surface thereon that is adapted to cause the desired operation of the valve mechanism of the recoil devices.

=- ,16. The combination with a cannon, and

fluid recoil-checking devices, of a guide ad- 'justable about an axis extending arallel to the length of the gun and provi ed with a plurality of longitudinally-extending curves or cam-surfaces, means for operating the valve mechanism of the recoil devices including a part adapted to reciprocate with the gun in contact with said guide, a rack adapted to move longitudinally as the elevation of dle supporting the cannon and on which it is adapted to reciprocate, and fluid recoil-checking devices, of a uide mounted on the cradle and adjustable about a lon itudinal axis, said guide having a plurality of on itudinally-extending cam-surfaces formed t ereon, means for operating the valve mechanism of the recoil devices including a part adapted to reciprocatewith the gun incontact with said guide, a shaft mounted in bearings on the cradle and geared to said guide, a pinion mounted on said shaft, and means for driving said pinion as the elevation of the gun is varied, whereby to bring diflerent cam-surfaces thereon successively into operative position as the elevation of the gun is varied.

18. The combination with a cannon, a cradle supporting the cannon and on which it is adapted to reciprocate, and fluid recoil-checking devices, of a guide mounted on the cradle and adjustable about a longitudinal axis, said guide. having a plurality of longitudinally-extending cam-surfaces formed thereon, means for operating the valve mechan i'sm of the recoil devices including a part adapted to reciprocate withithe gun in contact with said guide, a shaftmounted in bearings on the cradle and geared to said guide, a pinion mounted on said shaft, and intermittently-acting means for rotating said inion as the elevation of the gun is varied, su stantially as and for the purpose described.

19. The combination with a cannon, of fluid recoil-checking devices includin means for providing a fluid-passage of uni mensions'at the beginning of each recoil, and means for varyin the intervals of time ela sin between t e commencement of recoi an the instant the maximum passage is provided and the closing of said passage after reaching said maximum, as the elevation of the gun is varied.

20. The combination with a cannon, of fluid recoil-checking devices includin means for providing a fluid-passage of uni orm dimensions at the beginning of each recoil, and means for varying the maximum size of said orm disaid guide will be adjusted 7 passage and the intervals of time elapsing betweenthe commencement of said recoil and the instant said maximum is reached'and theclosing of said passage after said maximum as the elevation of the gun is varied.

21. The combination with a cannon and fluid recoil-checking devices, of a roller movable about an axis extending parallel to the length of the gun, means for so moving said roller during the recoil of the gun, means actuated by the rocking movement of said roller for operating the valve mechanism of the recoil-checking devices, and means for changing the extent of said rocking movement during recoil to vary the operation of said valve mechanism.

22. The combination with a cannon and fluid recoil-checking devices, of means includ-.

ing a plurality of elements, each adapted to control the recoil-checking devices and to cause said devices to act in a manner different fromfleitherof the others, and means for xbringing said elements successively into operative position as the eleyation of the'gun-is varied.

23. The combination with a cannon and fluid recoil-checking devices, of a rack adapted. to be moved longitudinally as the elevation of the gun is varied, and means adapted to be actuated by said rack for varying the port area of the valve mechanism of the recoil-checking devices during recoil, whereby the length of recoil will be automatically varied with variations in the elevation of the gun. V 24. The combination with a cannon and fluid recoil checking devices, of intermittingly-acting means for adjusting the valve mechanism of said checking devices in conformity with variations in the elevation of the gun. .25. The combination with a cannon and fluid recoil-checking devices, of a gear adapted to adjust the. valve mechanism of the recoil-checking devices to regulate the action of said checki l devices in conformity with variations in eevation of the gun, a rack for actuating said gear, and means for intercated as the elevation of the gun is changed, 1

means for normally preventing such reciprocation of the-rack, and means for intermit tingly Withdrawing said stop or lock means.

I 27. Thecombination with a suitable carriage, a gun mounted thereon, and a variablerecoil mechanism for the gun, comprising means for obtaining constantly-increasing pressures at the moments of recoil as the clevation of, the gun is increased, of means for uniformly decreasing the pressure during recoil, whereb the recoil will, be properly checked at al angles of elevation of the gun. a

28. The combination with a suitable carriage, a gun mounted thereon, and a variablerecoil mechanism for the un, comprising means for obtaining constant y-increasing re sistance at the moments of recoil asthe elevation of the gun is increased, of means for uniformly decreasing the pressure during'recoil, whereb the recoil will be properly checked at al angles of elevation oft e unv In testimony whereof I have-signe 'my name to this specification in the presence of two subscribing witnesses.

, FRANK B. YINGLING.

Witnesses: I 7

WILLIAM ESSENWEIX, PETER LIEBER. 

